How Long Do STIs Take to Show Up?

After unprotected sex or a condom mishap, it’s normal to feel anxious and want immediate reassurance. But here’s the challenge: sexually transmitted infections (STIs) don’t always show up right away on tests. Each infection has its own “window period” - the time between exposure and when it can be reliably detected.

Testing too soon could give you false reassurance, while waiting too long may allow the infection to progress. Here’s what you need to know about how long STIs take to show up.

What Is the Window Period?

The “window period” refers to the time between infection and when a test can detect it. During this period, you might already be contagious even if tests come back negative. That’s why timing your test correctly is so important.

How Long Different STIs Take to Show Up

Chlamydia

• Detectable from 1–2 weeks after exposure.
• Most people never develop symptoms, which makes testing vital.

Gonorrhoea

• Detectable from 1–2 weeks.
• Can infect the throat, rectum, or genitals, often without symptoms.

HIV

• 10 days onwards: Early detection tests (RNA/NAAT).
• 28 days onwards: Standard 4th-generation tests are reliable.
• 3 months: Final confirmation if high risk.

Syphilis

• Usually detectable from 3 weeks onwards.
• Some people may need to wait up to 12 weeks for the most accurate results.

Herpes (HSV)

• No reliable blood test for new infections.
• If sores develop, they can be tested straight away with a swab.

HPV (Human Papillomavirus)

• Often symptomless and may not be picked up immediately.
• Testing is generally offered through cervical screening programmes.

Hepatitis B & C

• Detectable from 4–6 weeks with blood tests.

Should You Test More Than Once?

Yes. A single test after possible exposure may not be enough. Many people choose to:

• Test at 2 weeks – for early detection of Chlamydia and Gonorrhoea.
• Test again at 4–6 weeks – for HIV, Syphilis, and Hepatitis.
• Repeat at 3 months – if exposure was high-risk, for complete reassurance.

👉 Get the right test at the right time with STI Clinic.

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Why Symptoms Aren’t Reliable

It’s tempting to wait and see if you develop symptoms. But many STIs stay silent:

• 70–80% of people with Chlamydia don’t notice symptoms.
• Gonorrhoea can easily be mistaken for a urinary infection.
• HIV may not cause signs for years.

That’s why relying on symptoms alone is risky.

What to Do If You’ve Recently Been Exposed

• Don’t panic. Not every encounter leads to infection.
• Book a consultation. A clinician can advise on urgent options like HIV post-exposure prophylaxis (PEP).
• Schedule your tests. Plan both an early screen and follow-up testing.
• Use protection going forward. Avoid unprotected sex until you have results.

👉 Book your confidential STI test at STI Clinic today for peace of mind.

Final Thoughts

So, how long do STIs take to show up? It depends on the infection:

• Some, like Chlamydia and Gonorrhoea, can be picked up in as little as two weeks.
• Others, like HIV and Syphilis, require longer before results are accurate.

The safest approach is a combination of early and follow-up testing. That way, you get fast reassurance while ensuring nothing is missed.

👉 Take control of your health. Arrange your STI screen now with STI Clinic.